This invention relates to an inflatable support, in particular an inflatable support that measures the movements of a patient supported on the support and adjusts the support provided depending on the movements detected.
There have been several techniques developed to measure body movement, patient entry and patient exit from a support using fluctuations in air pressure in the inflatable supports or inflatable bodies inserted between the patient and a supporting surface. The technique of measuring body movements by recording the air pressure in an air filled pad placed under a mattress was described by Kusunoki (1985). Another system has been developed to measure the respiratory movements of subjects by measuring pressure changes in a supporting air mattress (Hernandez 1995). U.S. Pat. No. 6,036,660 describes a system that uses transducers to detect and display movement in an air-filled cell or cells between a patient and a support.
Overall, these systems give a numerical or visual display of detected movement using the fluctuation of static air in an enclosed cell or cells. As there is a link between the rate of spontaneous body movements and the risk of developing pressure sores (Exton-Smith et al, 1961), the information provided or displayed helps in the assessment of the risk of pressure sore development. The information can be used to increase the manual turning of the patient or to aid the decision to move the patient to another support surface. Equally, the information can be completely ignored in a busy ward.